A known postural screening method involves a person/patient standing in a framework between a vertical plumb line and a vertically oriented, planar backdrop having a grid-work of vertical and horizontal lines. The medical practitioner performing the screening then observes postural deviations (mal-alignments) of the patient in the frontal plane, sagittal plane and transverse plane relative to the vertical and horizontal lines on the backdrop and the plumb line. The postural deviations observed are then recorded on a postural evaluation chart. The data from the postural evaluation can be input to a computer to aid in analysis in selection of a corrective exercise program, for example. U.S. Pat. No. 7,077,813 discloses such a system and method.
Drawbacks of the known method and system include that taking all the postural deviation measurements can be time consuming and imprecise. The screening must also be conducted in a facility having the required framework of vertical backdrop and plumb line. The known method and system are not readily movable and the method is not capable of being performed in another setting lacking these components. There is a need for an improved, mobile postural screening method and system which overcome these drawbacks and limitations. The present invention addresses this need.
The improved postural screening method according to the example embodiments of the present invention comprises acquiring an image of a patient on a display screen having an array of pixels, determining a pixel to distance ratio for the displayed image, and calculating a postural displacement of the patient in the displayed image using the determined ratio. The standing framework of vertical backdrop and plumb line of the prior art is not necessary. According to the disclosed method, a known linear distance in the displayed image and the number of display screen pixels spanning the distance are used in determining pixel to distance ratio. The known linear distance in an example embodiment is the height of the patient. Alternately, or in addition as a secondary calibration, a marked distance can be provided in the acquired image of the patient, as by the use of a meter stick in the image or other markings of a known distance apart, to provide a known linear distance.
The postural screening method in example embodiments further includes scaling the size of the image relative to the display screen to normalize the known linear distance in the image to a display screen reference distance corresponding to a known number of pixels for determining the pixel to distance ratio. According to a disclosed method, at least one reference line is provided over the displayed image to demark the display screen reference distance.
The method as disclosed herein further includes displaying a reference line overlaid on the screen providing vertical, horizontal and center references, providing a corresponding reference line anchored to the displayed patient's image, and adjusting the image in the display so that the two reference lines are aligned before determining the pixel to distance ratio.
The patient's image can be acquired by accessing a database. Alternatively, the person performing the screening can operate an image capture device of a camera for acquiring the image of the patient. The method preferably includes leveling the image capture device before capturing the image from which the pixel to distance ratio is to be determined for eliminating distortion. According to the example embodiments, the image capture device and display screen are part of a mobile, hand-held communication device having at least one positional device selected from the group consisting a gyroscope, an accelerometer, and a level. The method includes activating the at least one positional device and using an output thereof to provide a reference for leveling the image capturing device.
In disclosed embodiments, the method further includes displaying a reference line on the display screen over the acquired image, performing panning to center the image on the screen, and performing zooming to fit the image in the reference line before determining the pixel to distance ratio. Still further, the method comprises providing anatomical landmarks on the acquired image of the patient to facilitate calculating a postural displacement. The display screen is a touch screen for this purpose to identify coordinates for calculation of postural displacements by the programmed computer of the mobile, hand-held communication device.
A system for performing postural screening according to the invention comprises means for acquiring an image of a patient on a display screen having an array of pixels, means for determining a pixel to distance ratio for the displayed image and means for calculating a postural displacement of the patient in the displayed image using the determined ratio. The means for acquiring an image of a patient according to an example embodiment includes an image capture device of the mobile, programmed, hand-held communication device. Preferably, the device includes at least one positional device selected from the group consisting of a gyroscope, an accelerometer, and a level which provides a reference for leveling the image capturing device. The system further includes means for panning a displayed image on the screen to center the image on the screen, and means for zooming to fit a displayed image in a reference line on the display screen. Means are provided for displaying at least one reference line over the displayed image to demark a display screen reference distance corresponding to a known number of pixels for determining the pixel to distance ratio.
The system of the disclosed embodiments further includes means for displaying a reference line overlaid on the screen providing vertical, horizontal and center references, means for displaying a corresponding reference line anchored to the displayed patient's image, and means for aligning image and display screen reference lines before determining the pixel to distance ratio. The system further includes means for providing anatomical landmarks on the acquired image of the patient to facilitate calculating a postural displacement.
The present invention further includes a machine-readable medium containing at least one sequence of instructions that, when executed, causes a machine to: calculate at least one postural displacement of a patient from a displayed image of the patient on a display screen having an array of pixels, using a determined pixel to distance ratio for the displayed image.
These and other objects, features and advantages of the invention will become more apparent from the following detailed description of example embodiments taken with the accompanying drawings.